I don't know why the heavier springs were used, but all I can say is that when I first bought the car I was amazed with the ride and control. I had nothing to compare it to except the Caddy we owned which was pathetic. I am going to have my mechanic check my front tires and if the wear is 100% even I think I will save my money for now, unless someone can give me a compelling reason to run out and get correct springs from the dealer tomorrow morning before the car is put back together again.
1995 E420 - retired
1986 420SEL - retired